The Fukushima Daiichi Nuclear Power Plant (IF) Unit I to 3 in Japan, owned and operated by Tokyo Electric Power Company (TEPCO), suffered tremendous damage from the East Japan Great Earthquake that occurred on Mar. 11, 2011. It is assumed that nuclear fuels in the 1F reactors experienced melting and, as a result, dropped to the bottom of the Reactor Pressure Vessel (RPV) and/or Pressure Containment Vessel (PCV), solidifying there as fuel debris after being fused with reactor internals, concrete structures, and other materials.
In order to pursue decommissioning of 1F, it is necessary to remove the fuel debris from the RPV/PCV using appropriate and safe Packaging, Transfer and Storage (PTS) procedures. Fuel debris retrieval procedures are expected to be started within 10 years' time and completed in 20 to 25 years' time. It is planned that after 30-40 years the fuel debris will all be placed in interim storage.